Do splitters for mac combined mic/headphones exist?

I am looking for a splitter that turns my 3.5mm headphone and mic port on my Mac mini into two 3.5mm headphone and mic ports or one audio out port and one audio out/mic port.

I want to be able to leave my speakers plugged in and use my headphones/mic at the the same time. I will turn off speakers when using headphones and mic, but don't want to keep reaching around to plug and unplug.

I was unable to find anything that does what I want. Most splitters seem to only split the combined port into one audio out and one mic port.

How about the "Wiretap" from Extrasensory devices?

_{(source: shopify.com)}